Why we need to promote the Safe System Solution
May 2024
AITPM members enjoyed a thought-provoking webinar on the Safe System Approach to traffic management during National Road Safety Week.
The webinar, held on May 7, featured transport engineer Dr Jason Deller from Advanced Mobility Analytics Group, and Professor Shimul Haque, a specialist in econometrics and AI applications in traffic engineering and transport safety from the Queensland University of Technology (QUT).
The safe system approach adopts a holistic view of the road transport system and the interactions between people, vehicles, and the road environment. The approach recognises that people will always make mistakes and may have road crashes – but those crashes should not result in death or serious injury.
In his introduction, Dr Deller conceded that some of the audience may never have heard of safe systems, adding that this reflected the approach was not embraced strongly enough by the sector.
“The safe system is not new – it has been around for a couple of decades now and it shows how long it takes for this thinking to embed itself into organisations,” Dr Deller said. “It must come from the top and filter down.
“Vehicles are improving in safety enormously, but we are still seeing fatalities and serious injuries occurring. We know that they are not trending in the direction we want. A massive change needs to happen.”
The presentation explained the approach, what it looks like in the real world and solutions, including AI-based video analytics, together with traffic conflict techniques,
Dr Deller said that at is core, the safe system accepted that humans make mistakes and that our bodies are vulnerable.
“Until safe systems entered our minds, we focused responsibility on those users,” he said. “But now we know that humans will make mistakes but when they do, the system and the environment is such that they don't end up with fatalities and serious injuries because the system is safer.”
Dr Deller explained that many transport organisations had developed ‘cultural maturity’ and appreciated that zero deaths on roads was a possibility.
Professor Haque said in the past, transport safety organisations had mostly relied upon crash data to evaluate road safety – but AI tools were helping to change this.
“The real challenge is that crashes are rare and random events – we need to wait for crashes to happen before a location can be treated for solutions,” he said. “Crash location data is helpful, but it does not offer us much information about the road behaviour.”
Professor Haque told the webinar that his team had been developing AI models that convert road users captured in video – passenger cars, cyclists, heavy vehicles, scooters, and more – into vehicle trajectories to estimate the risk of crashes.
“We can pinpoint where traffic conflicts have occurred repeatedly with heat maps and identify the user behaviour,” he said. “We can look for repeated patterns and then develop solutions. The only way of moving forward is to embrace the technology to help us.”
Professor Haque also demonstrated a use-case of part-time protected right-turn signals for signalised intersections as a Safe System Solution. This new signal system allows permissive right-turn signals during peak hours and protected right-turn signals during off-peak hours.
In a before-after study in partnership with QUT, the Department of Transport and Main Roads and Advanced Mobility Analytics Group, Professor Haque demonstrated that part-time protected right-turn signals offer significant safety benefits in reducing right-turn crash risks without compromising operational efficiencies.
The webinar was developed by the Safety Task Group set up under the AITPM Inclusive Mobility Program. The Safe System approach is an area of focus for the group as it seeks to increase discussion on the challenges and opportunities to create positive action in the transport community.
Members of AITPM can view the webinar on demand - Click to view.